Abstract: A connection bolt (1) for repeated tightening beyond yield point which bolt (1) comprises a head (2) and a shank which shank is provided with a thread, whereby said head (2) of said connection bolt (1) is provided with at least one indication mark (9) at a fixed defined mutual angle position to at least one indication sign (10), which sign (10) is provided on the free shank (5) end relative to the axis (q—q) of the bolt (1) rotation. This system of marking allows to determine the damage of said bolt (1) exactly and to decide about further ability of said bolt (1) to be used next time without any risk of destruction or decrease in quality of a joint.

Abstract: Gearing mechanism particularly for changing the relative angular position of two parts. A crown or ring gear with internal toothing is pressed from a sheet forming one arm, and a spur gear with external toothing is pressed from a sheet forming a second arm. The connection between the first arm and a hub of the crown gear and between the second arm and the spur gear is accomplished by bridges formed at tooth gaps of a width of at least of one pitch of the toothings. The mechanism can be used with collapsible seats of vehicles, for head rests, for the raising and lowering of windows, in textile machines, childs' vehicles, in furniture, agricultural machines, and the like.